Standing Waves in a Nonuniform Medium

• Autores: Paul Gluck
• Localización: The Physics Teacher, ISSN 0031-921X, Vol. 49, Nº. 2, 2011, págs. 76-77
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • A recent note in this journal1presented a demonstration of standing waves along a cord consisting of two parts having different material densities, showing different sized wavelengths in each part. A generalization of that experiment to a continuously varying linear mass density is to vibrate a strip of material with gradually varying width mass per unit length, in order to show that as the strip gets wider, the wavelength becomes shorter. Figure 1 shows the setup. It consists of a mechanical driver fed by a signal generator, and a strip of flexible fabric connected at its narrow end to the driver, nailed to a suitable piece of wood at the wider end. The strip is in the shape of a trapeze, 2 cm and 10 cm at its ends and some 50 cm long in its middle. It may be cut from the inner tube of a tire, or from bodybuilding elastic strips.